Front (Inner facing) speaker part on Earpods doesn't work? No bass?

So I recently purchased a new iPhone 5 which came with the Earpods. Now, when i first bought them I was very happy with them. However, I have now encountered a problem which has really let me down.. The inner part (inner ear facing) speaker area doesnt output any sound at all I dont think. I hear no bass. This has only happened in my left headphone and I can assure you I have looked after them well. They are almost brand new too. Any ideas?